在碳纤维布上原位生长NiCo层状双氢氧化物纳米片用于高性能非对称超级电容器

通过恒电压电沉积法在不同的碳纤维基体上原位制备NiCo层状双金属氢氧化物(NiCo-LDH)复合材料(NiCo-LDH/碳纤维布),该方法无需粘合剂,可以有效避免由于粘合剂的加入引起的导电性降低。在NiCo-LDH的层状晶体结构中,正电荷的主体层和层间电荷补偿阴离子可以促进电极材料之间的离子扩散,从而可高效利用活性位点。得益于NiCo-LDH折叠层状结构的特点,NiCo-LDH/碳纤维布具有出色的比电容(1 A·g^-1时1387.5 F·g^-1)。此外,以NiCo-LDH/碳纤维布作为正极,涂覆在泡沫镍表面的还原氧化石墨烯(rGO/NF)作为负极,组装而成的非对称超级电容器(ASC)具有极好的电化学性能。ASC在1 A·g^-1时能量密度为26.6 Wh·kg^-1,功率密度为850.4 W·kg^-1,在最大功率密度为8500.3 W·kg^-1时能量密度仍保持有14.9 Wh·kg^-1。

In-Situ Growth of NiCo-Layered Double Hydroxides Nanosheets Deposited on Carbon Fiber Cloth for High-Performance Asymmetric Supercapacitors

The NiCo-layered double hydroxide (LDH) was prepared directly on different carbon fiber substrates by potentiostatic deposition. This method did not need to add any binder, which can prevent the phenomenon of conductivity reduction due to the resistance of the binder. In the layered crystal structure of NiCo-LDH, the positively charged host layer and the interlayer charge compensating anion can promote ion diffusion between electrode materials, so that the active sites can be efficiently utilized. In this paper, an electrode material with a wrinkled structure was synthesized by a potentiostatic deposition technique. Benefiting from the folded lamellar structure features, this composite material (NiCo-LDH/carbon fiber cloth) had sterling specific capacitance (1 387.5 F·g^-1 at 1 A·g^-1). In addition, with the composite as the positive electrode and the rGO coated on the surface of nickel foam (NF) as negative material, the assembled asymmetric supercapacitor (ASC) presented superb electrochemical performance. ASC had an energy density of 26.6 Wh·kg^-1 and a power density of 850.4 W·kg^-1 at 1 A·g^-1. The energy density remained 14.9 Wh·kg^-1 as the maximum power density (8 500.3 W·kg^-1).